2 * Driver for s390 eadm subchannels
4 * Copyright IBM Corp. 2012
5 * Author(s): Sebastian Ott <sebott@linux.vnet.ibm.com>
8 #include <linux/kernel_stat.h>
9 #include <linux/completion.h>
10 #include <linux/workqueue.h>
11 #include <linux/spinlock.h>
12 #include <linux/device.h>
13 #include <linux/module.h>
14 #include <linux/timer.h>
15 #include <linux/slab.h>
16 #include <linux/list.h>
18 #include <asm/css_chars.h>
19 #include <asm/debug.h>
31 MODULE_DESCRIPTION("driver for s390 eadm subchannels");
32 MODULE_LICENSE("GPL");
34 #define EADM_TIMEOUT (7 * HZ)
35 static DEFINE_SPINLOCK(list_lock
);
36 static LIST_HEAD(eadm_list
);
38 static debug_info_t
*eadm_debug
;
40 #define EADM_LOG(imp, txt) do { \
41 debug_text_event(eadm_debug, imp, txt); \
44 static void EADM_LOG_HEX(int level
, void *data
, int length
)
46 debug_event(eadm_debug
, level
, data
, length
);
49 static void orb_init(union orb
*orb
)
51 memset(orb
, 0, sizeof(union orb
));
52 orb
->eadm
.compat1
= 1;
53 orb
->eadm
.compat2
= 1;
58 static int eadm_subchannel_start(struct subchannel
*sch
, struct aob
*aob
)
60 union orb
*orb
= &get_eadm_private(sch
)->orb
;
64 orb
->eadm
.aob
= (u32
)__pa(aob
);
65 orb
->eadm
.intparm
= (u32
)(addr_t
)sch
;
66 orb
->eadm
.key
= PAGE_DEFAULT_KEY
>> 4;
69 EADM_LOG_HEX(6, &sch
->schid
, sizeof(sch
->schid
));
71 cc
= ssch(sch
->schid
, orb
);
74 sch
->schib
.scsw
.eadm
.actl
|= SCSW_ACTL_START_PEND
;
76 case 1: /* status pending */
79 case 3: /* not operational */
85 static int eadm_subchannel_clear(struct subchannel
*sch
)
89 cc
= csch(sch
->schid
);
93 sch
->schib
.scsw
.eadm
.actl
|= SCSW_ACTL_CLEAR_PEND
;
97 static void eadm_subchannel_timeout(struct timer_list
*t
)
99 struct eadm_private
*private = from_timer(private, t
, timer
);
100 struct subchannel
*sch
= private->sch
;
102 spin_lock_irq(sch
->lock
);
103 EADM_LOG(1, "timeout");
104 EADM_LOG_HEX(1, &sch
->schid
, sizeof(sch
->schid
));
105 if (eadm_subchannel_clear(sch
))
106 EADM_LOG(0, "clear failed");
107 spin_unlock_irq(sch
->lock
);
110 static void eadm_subchannel_set_timeout(struct subchannel
*sch
, int expires
)
112 struct eadm_private
*private = get_eadm_private(sch
);
115 del_timer(&private->timer
);
118 if (timer_pending(&private->timer
)) {
119 if (mod_timer(&private->timer
, jiffies
+ expires
))
122 private->timer
.expires
= jiffies
+ expires
;
123 add_timer(&private->timer
);
126 static void eadm_subchannel_irq(struct subchannel
*sch
)
128 struct eadm_private
*private = get_eadm_private(sch
);
129 struct eadm_scsw
*scsw
= &sch
->schib
.scsw
.eadm
;
130 struct irb
*irb
= this_cpu_ptr(&cio_irb
);
131 blk_status_t error
= BLK_STS_OK
;
134 EADM_LOG_HEX(6, irb
, sizeof(*irb
));
136 inc_irq_stat(IRQIO_ADM
);
138 if ((scsw
->stctl
& (SCSW_STCTL_ALERT_STATUS
| SCSW_STCTL_STATUS_PEND
))
139 && scsw
->eswf
== 1 && irb
->esw
.eadm
.erw
.r
)
140 error
= BLK_STS_IOERR
;
142 if (scsw
->fctl
& SCSW_FCTL_CLEAR_FUNC
)
143 error
= BLK_STS_TIMEOUT
;
145 eadm_subchannel_set_timeout(sch
, 0);
147 if (private->state
!= EADM_BUSY
) {
148 EADM_LOG(1, "irq unsol");
149 EADM_LOG_HEX(1, irb
, sizeof(*irb
));
150 private->state
= EADM_NOT_OPER
;
151 css_sched_sch_todo(sch
, SCH_TODO_EVAL
);
154 scm_irq_handler((struct aob
*)(unsigned long)scsw
->aob
, error
);
155 private->state
= EADM_IDLE
;
157 if (private->completion
)
158 complete(private->completion
);
161 static struct subchannel
*eadm_get_idle_sch(void)
163 struct eadm_private
*private;
164 struct subchannel
*sch
;
167 spin_lock_irqsave(&list_lock
, flags
);
168 list_for_each_entry(private, &eadm_list
, head
) {
170 spin_lock(sch
->lock
);
171 if (private->state
== EADM_IDLE
) {
172 private->state
= EADM_BUSY
;
173 list_move_tail(&private->head
, &eadm_list
);
174 spin_unlock(sch
->lock
);
175 spin_unlock_irqrestore(&list_lock
, flags
);
179 spin_unlock(sch
->lock
);
181 spin_unlock_irqrestore(&list_lock
, flags
);
186 int eadm_start_aob(struct aob
*aob
)
188 struct eadm_private
*private;
189 struct subchannel
*sch
;
193 sch
= eadm_get_idle_sch();
197 spin_lock_irqsave(sch
->lock
, flags
);
198 eadm_subchannel_set_timeout(sch
, EADM_TIMEOUT
);
199 ret
= eadm_subchannel_start(sch
, aob
);
203 /* Handle start subchannel failure. */
204 eadm_subchannel_set_timeout(sch
, 0);
205 private = get_eadm_private(sch
);
206 private->state
= EADM_NOT_OPER
;
207 css_sched_sch_todo(sch
, SCH_TODO_EVAL
);
210 spin_unlock_irqrestore(sch
->lock
, flags
);
214 EXPORT_SYMBOL_GPL(eadm_start_aob
);
216 static int eadm_subchannel_probe(struct subchannel
*sch
)
218 struct eadm_private
*private;
221 private = kzalloc(sizeof(*private), GFP_KERNEL
| GFP_DMA
);
225 INIT_LIST_HEAD(&private->head
);
226 timer_setup(&private->timer
, eadm_subchannel_timeout
, 0);
228 spin_lock_irq(sch
->lock
);
229 set_eadm_private(sch
, private);
230 private->state
= EADM_IDLE
;
232 sch
->isc
= EADM_SCH_ISC
;
233 ret
= cio_enable_subchannel(sch
, (u32
)(unsigned long)sch
);
235 set_eadm_private(sch
, NULL
);
236 spin_unlock_irq(sch
->lock
);
240 spin_unlock_irq(sch
->lock
);
242 spin_lock_irq(&list_lock
);
243 list_add(&private->head
, &eadm_list
);
244 spin_unlock_irq(&list_lock
);
246 if (dev_get_uevent_suppress(&sch
->dev
)) {
247 dev_set_uevent_suppress(&sch
->dev
, 0);
248 kobject_uevent(&sch
->dev
.kobj
, KOBJ_ADD
);
254 static void eadm_quiesce(struct subchannel
*sch
)
256 struct eadm_private
*private = get_eadm_private(sch
);
257 DECLARE_COMPLETION_ONSTACK(completion
);
260 spin_lock_irq(sch
->lock
);
261 if (private->state
!= EADM_BUSY
)
264 if (eadm_subchannel_clear(sch
))
267 private->completion
= &completion
;
268 spin_unlock_irq(sch
->lock
);
270 wait_for_completion_io(&completion
);
272 spin_lock_irq(sch
->lock
);
273 private->completion
= NULL
;
276 eadm_subchannel_set_timeout(sch
, 0);
278 ret
= cio_disable_subchannel(sch
);
279 } while (ret
== -EBUSY
);
281 spin_unlock_irq(sch
->lock
);
284 static int eadm_subchannel_remove(struct subchannel
*sch
)
286 struct eadm_private
*private = get_eadm_private(sch
);
288 spin_lock_irq(&list_lock
);
289 list_del(&private->head
);
290 spin_unlock_irq(&list_lock
);
294 spin_lock_irq(sch
->lock
);
295 set_eadm_private(sch
, NULL
);
296 spin_unlock_irq(sch
->lock
);
303 static void eadm_subchannel_shutdown(struct subchannel
*sch
)
308 static int eadm_subchannel_freeze(struct subchannel
*sch
)
310 return cio_disable_subchannel(sch
);
313 static int eadm_subchannel_restore(struct subchannel
*sch
)
315 return cio_enable_subchannel(sch
, (u32
)(unsigned long)sch
);
319 * eadm_subchannel_sch_event - process subchannel event
321 * @process: non-zero if function is called in process context
323 * An unspecified event occurred for this subchannel. Adjust data according
324 * to the current operational state of the subchannel. Return zero when the
325 * event has been handled sufficiently or -EAGAIN when this function should
326 * be called again in process context.
328 static int eadm_subchannel_sch_event(struct subchannel
*sch
, int process
)
330 struct eadm_private
*private;
333 spin_lock_irqsave(sch
->lock
, flags
);
334 if (!device_is_registered(&sch
->dev
))
337 if (work_pending(&sch
->todo_work
))
340 if (cio_update_schib(sch
)) {
341 css_sched_sch_todo(sch
, SCH_TODO_UNREG
);
344 private = get_eadm_private(sch
);
345 if (private->state
== EADM_NOT_OPER
)
346 private->state
= EADM_IDLE
;
349 spin_unlock_irqrestore(sch
->lock
, flags
);
354 static struct css_device_id eadm_subchannel_ids
[] = {
355 { .match_flags
= 0x1, .type
= SUBCHANNEL_TYPE_ADM
, },
356 { /* end of list */ },
358 MODULE_DEVICE_TABLE(css
, eadm_subchannel_ids
);
360 static struct css_driver eadm_subchannel_driver
= {
362 .name
= "eadm_subchannel",
363 .owner
= THIS_MODULE
,
365 .subchannel_type
= eadm_subchannel_ids
,
366 .irq
= eadm_subchannel_irq
,
367 .probe
= eadm_subchannel_probe
,
368 .remove
= eadm_subchannel_remove
,
369 .shutdown
= eadm_subchannel_shutdown
,
370 .sch_event
= eadm_subchannel_sch_event
,
371 .freeze
= eadm_subchannel_freeze
,
372 .thaw
= eadm_subchannel_restore
,
373 .restore
= eadm_subchannel_restore
,
376 static int __init
eadm_sch_init(void)
380 if (!css_general_characteristics
.eadm
)
383 eadm_debug
= debug_register("eadm_log", 16, 1, 16);
387 debug_register_view(eadm_debug
, &debug_hex_ascii_view
);
388 debug_set_level(eadm_debug
, 2);
390 isc_register(EADM_SCH_ISC
);
391 ret
= css_driver_register(&eadm_subchannel_driver
);
398 isc_unregister(EADM_SCH_ISC
);
399 debug_unregister(eadm_debug
);
403 static void __exit
eadm_sch_exit(void)
405 css_driver_unregister(&eadm_subchannel_driver
);
406 isc_unregister(EADM_SCH_ISC
);
407 debug_unregister(eadm_debug
);
409 module_init(eadm_sch_init
);
410 module_exit(eadm_sch_exit
);